Protractor.



UNIT

s r'rs FAWCETT H. COLPI'ITS, OF GATES, OREGON.

PROTRAGTOR.

Application filed October 3,

To all whom it m (13 concern Be it known that I, FAwon'r'r H. Conrrrrs,a citizen of Great Britain, residing at Gates, in the county of Marionand State of Oregon, have invented certain new and useful Improvementsin Protractors; and I do hereby declare the followin to be a full,clear, and exact description OI the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

This invention relates to new and useful improvements in protractors,and has for its principal object to provide a simple device of thischaracter whereby lines may be drawn at any given angle to each otherand at any desired distance from a given point without moving the bodyof the protractor from a fixed position.

Heretofore it. has been customary in the use of protractors, to placethe same upon a T square and mark the angle to which the line is to bedrawn, using a triangle for this purpose.

The object. of the present invention is to overcome this objectionablefeature and form a construction whereby the angle may be drawnabsolutely independent of the triangle, and at the same time produce anaccurate drawing.

\Vith the above and other objects in view, this invention consists inthe construction, combination and arrangement of parts, all ashereinafter more fully described, claimed and illustrated in theaccompanying drawings. wherein:

Figure 1 is an elevation illustrating a protractor constructed inaccordance with the present. invention; and Fig. 2- is a section takenalong line 2 2 of Fig. 1.

The protractor forming the subject matter of the present inventioncomprises a protractor of the usual construction, having a semi-circularplat-e provided with graduations thereon. A main supporting member orrule is pivoted or otherwise secured centrally to the body of theprotractor, and is provided at the terminal thereof adjacent tothegraduations of said protractor with an indicator. A plurality of linksare pivotally connected to the main body of the supporting member orrule,

Copies of this patent may be obtained for five cents Specification ofLetters Patent.

Patented May 5, 1914:.

1911. Serial No. 652,608.

and carry a rule at the terminal thereof at each side of the mainsupporting member, said rules being adapted to be at all times parallelto said member. Each rule is pro vided with a graduated rule slidablymounted on the upper surface thereof, as is specifically illustrated inFig. 2.

Reference being had more particularly to the drawings, 10 indicates aprotractor of any suitable construction, provided with a semi-circulargraduated disk 10% A central or main supporting rule 11 is pivoted tothe protractor 10, and is provided at its outer terminal with anindicator. 11, which cooperates with the graduations 10" on theprotractor. A plurality of rules 12 are pivotally connected to the mainsupporting rule 11, tl'irough the instrumentality of the links 13, whichare pivotally connected to said rules 12, and are adapted to retain thesame constantly parallel to the main supporting rule 11. A graduatedrule 1% is reciprocatingly mounted upon each rule 12 thereof, throughthe instrumentality of the slots 15 which receive the pins connectingthe links 13 to the rules 12.

Having thus fully described my invention, what I claim as new and desireto secure by U. S. Letters Patent, is:

:1 protractor comprising a semi-circular plate having graduations uponits curved edge, a rule pivoted centrally to the straight edge of saidsemi-circular plate, an indicator secured to the terminal of said ruleadjacent the graduations on said plate, a pair of equal links pivoted attheir extremities to each side of said rule adjacent the ends thereof, asecond rule having a graduated rule reciiprocatinglv mounted thereonsecured to each pair of links at points spaced apart a distanceequivalent to the len th of the first mentioned rule, whereby lines maybe drawn at any given angle to each other and at any desired distancefrom a given pointwithout moving the semi-circular plate and firstmentioned rule from a fixed position.

In testimony whereof I affix my signature in presence of two witnesses.

FAVCETT H. COLPXTTS. Witnesses CEOILE KNOX,

C. E. Son.

each, by addressing the Commissioner of Patents,

Washington, D. G.

